Process for the Treatment of Biological Materials and Wastewater

ABSTRACT

A process in which a waste stream containing microbes and organic constituents is passed through a process environment comprising a solid media, microbes, and higher animals, such that some of the microbes and/or organic constituents within the waste stream are removed from the waste stream and some of the removed microbes are destroyed or consumed by the higher animals. The process environment may include an irrigated environment, a submerged environment, or a combined environment.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 13/821,744 filed on Jul. 25, 2013, which is theU.S. National Stage of application No. PCT/US2011/051200 filed on Sep.12, 2011, which claims priority to U.S. Provisional Application No.61/381,658, filed Sep. 10, 2010 entitled “Process for the Treatment ofBiological Materials and Wastewater”, the entire disclosures of whichare herein incorporated by reference.

BACKGROUND OF THE INVENTION Field of the Invention

The invention relates to a system for treatment of biological materialsand wastewater and, more particularly, a system for the separation ofmicrobial biomass from an aqueous liquid from which it was produced.

Description of Related Art

The biological treatment of aqueous liquids containing organic materialsand nutrients has been employed in many different configurations forwell over 100 years. Applications include food production, agriculture,wastewater treatment, pharmaceuticals preparation, and the like. Most ofthese applications involve the growth of microorganisms, principallybacteria, which bioconvert the organic materials and nutrients in theaqueous liquids into carbon dioxide, water, various other products, andmicrobial cell biomass. The microorganisms usually are grown insuspended growth systems or in fixed film systems. Virtually all ofthese processes produce a biological mass, and this biological mass isoften associated with other materials such as particulate solids orother non soluble materials that are present in the aqueous liquids.Often, it is desirable to separate the biological masses, and associatedparticulate and non-soluble materials, from the aqueous liquids beingtreated. This may occur after or during the treatment process itself.

There are many different processes for performing such separations.Commonly used procedures include gravity settling or floatation, or awide variety of mechanical procedures involving filtration,centrifugation, screening, and the like. Such processes and proceduresproduce a mixture of biological masses and associated particulate andnon-soluble materials, which are often termed “sludge”, which must beperiodically removed from the treatment or production process andutilized or disposed of in some manner. Methods of disposal of sludgethat are commonly used include land application, containment inlandfills, incineration with disposal or reuse of ash, or similarmethods.

Prior to disposal, it is often common for biological sludge to bestabilized by one or more stabilization processes. These processes aredesigned to reduce the volatile content of the sludge, reduce the volumeof the sludge, destroy pathogens, reduce or minimize the likelihood thatbacteria can grow in the processed sludge, and to reduce or eliminateodors.

Two processes commonly used for biosolid sludge stabilization includeaerobic digestion or anaerobic digestion. These two processes usemicroorganisms, mostly bacteria, to bioconvert organic materials in thebiosolids into carbon dioxide and water, and in the case of anaerobicdigestion, methane. After all or most of the biosolids material has beenreacted, both processes produce a microbial biomass which is either notsusceptible to further reaction, or which only reacts relatively slowlycompared with the design performance of the basic stabilizationprocesses.

This stabilized sludge or microbial biomass contains bacteria and othermicroorganisms which contain significant amounts of carbon and nutrientssuch as nitrogen, phosphorus, and the like. The carbonaceous materialsand nutrients that are constituents of these organisms are generallyimpervious to further action by either the wastewater treatment or otherprocess from which they were obtained, or to the anaerobic or aerobicdigestion processes which may have been used to stabilized them. Hencethey must be removed from the treated liquid stream and be disposed ofin a suitable manner.

SUMMARY OF THE INVENTION

In accordance with an embodiment of the invention, a process including awaste stream containing microbes and organic constituents is passedthrough a process environment comprising a solid media, microbes andhigher animals, such that some of the microbes and/or organicconstituents within the waste stream are removed from the waste streamand some of the removed microbes are destroyed or consumed by the higheranimals.

The process environment may be an irrigated environment. In anotherconfiguration, the process environment may be a submerged environment.In yet another embodiment, the process environment is a combinedenvironment comprising an irrigated environment and a submergedenvironment.

The waste stream may be an effluent stream from at least one of anactivated sludge wastewater treatment system, a biological nutrientremoval treatment system, a confined animal facility operation, a foodprocessing facility, and/or a pharmaceutical processing facility.Optionally, the waste stream may include animal manure.

In one embodiment, at least some of the liquid exiting the processenvironment having a first total solids value is recycled into theprocess environment for further treatment. In another embodiment, theliquid exiting the process environment after being recycled into theprocess environment has a second total solids value, the second totalsolids value being less than the first total solids value.

The process of the present invention may also include a low oxygennitrification-denitrification bioreactor in communication with the wastestream. Optionally, the process may include a second low oxygennitrification-denitrification bioreactor in communication with the wastestream.

In certain configurations, the higher animals produce at least somenitrogenous waste and the nitrification-denitrification system convertsat least some of the nitrogenous waste to dimolecular nitrogen that isdischarged to atmosphere. In other configurations, the process includesan organism collector in flow communication with the waste stream of theprocess environment to remove at least some higher animals from theprocess environment. Optionally, the waste stream may include at leastsome solid material. In another configuration, the process environmentincludes an irrigated biofilter.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic representation of an irrigated environment incommunication with a treatment or production system in accordance withan embodiment of the present invention.

FIG. 2 is a schematic representation of a submerged environment incommunication with a treatment or production system in accordance withan embodiment of the present invention.

FIG. 3 is a schematic representation of a containment structure suitablefor use in the submerged environment in accordance with an embodiment ofthe present invention.

FIG. 4 is a schematic representation of a combined environment incommunication with a treatment or production system in accordance withan embodiment of the present invention.

FIG. 5 is a schematic representation of an activated sludge municipalwaste treatment system in communication with a treatment or productionsystem in accordance with an embodiment of the present invention.

FIG. 6 is a schematic representation of a system for treating animalmanure in communication with a treatment or production system inaccordance with an embodiment of the present invention.

FIG. 7 is a schematic representation of a system for treating animalmanure including a multi-stage activated sludge system in communicationwith a treatment or production system in accordance with an embodimentof the present invention.

FIG. 8 is a schematic representation of a system for treating animalmanure including a second low oxygen nitrification-denitrificationbioreactor in communication with a treatment or production system inaccordance with an embodiment of the present invention.

FIG. 9 is a schematic representation of a system for treating animalmanure including the second low oxygen nitrification-denitrificationbioreactor of FIG. 8, and having the initial bioreactor removedtherefrom, in communication with a treatment or production system inaccordance with an embodiment of the present invention.

FIG. 10 is a schematic representation of a direct flow environment incommunication with a treatment or production system in accordance withan embodiment of the present invention.

DETAILED DESCRIPTION

The present invention is directed to a process in which excess sludge ormicrobial biomass, either stabilized or unstabilized, can be separatedfrom an aqueous liquid from which it was produced or obtained,collected, and further processed. This additional processing may produceadditional products, some of which may have significant value, and anadditional waste stream containing dead bacteria and organic fragmentsresulting from the death of bacteria. The resulting waste stream can bereintroduced back into the wastewater treatment process, or back intothe stabilization process, from which its material was originallyobtained, or into a new treatment process, for further treatment. Thisprocess applies to both stabilized and unstabilized sludges andbiomasses.

In accordance with an embodiment of the present invention, the systemwill include introducing a microbial biomass or biosolid containingmicroorganisms, and in particular bacteria, into an environment wherethey can be consumed by higher organisms. These higher organisms couldrange from protozoa, to any of a variety of invertebrates such as worms,insects, snails, crustaceans, or the like, or to various vertebratessuch as fish, turtles, amphibians, reptiles, birds, or mammals.

The environment containing the higher organisms may include conventionalfixed film processes, suspended growth processes, or a combination ofboth processes. The fixed film processes may be supported bybiodegradable material such as wood chips, sawdust, various agriculturalwaste materials, or the like, or by other media which is not itselfbiodegradable but is supportive of microbial growth on its surfaces.This environment may act as a filter in that both the microbesthemselves and the biological masses, and associated particulate andnon-soluble materials, may be removed from the aqueous liquid. In oneembodiment of the invention, the particulate and non-soluble materialswhich are separated from the aqueous liquid themselves become part ofthe fixed film media. These materials then provide surfaces foradditional microbial growth and act to further remove new biologicalmasses and associated particulate and non-soluble materials.

The suspended growth processes may comprise a variety of biologicalflocs containing microorganisms, invertebrates, and a variety of otherbiological substances and associated particulate and non-solublematerials. The microorganisms may comprise bacteria, protozoa, algae,and other plants and animals.

Once the biosolid or microbial biomass has been consumed by the higherorganisms, part of the cellular structures of the microorganisms will bedestroyed by the ingesting organism, and some of the carbonaceousmaterial and nutrients will be converted into the biomass of theconsuming higher organisms for growth and reproduction. The remainder ofthese materials will be excreted by the higher organisms.

The excreta of the higher organisms contains materials that can onceagain be successfully treated by the originating wastewater treatment orother production processes or by the biological processes used tostabilize the original biosolids or microbial biomasses. This may reducethe total volume and weight of material which ultimately must bedisposed of by landfilling, land application, incineration, or the like.

The higher organisms which also result from the process of the inventioncan then be collected for removal or other use such as feed for animals,soil conditioners, or the like. Any partially degraded organic materialused in the fixed film processes, such as wood chips, sawdust, variousagricultural waste materials, or the like, can be separated from themicrobial biomasses, invertebrates, or other animals and used an energysource.

The process of the invention can be applied to any biological waste orwastewater treatment process used for the reduction of suspended solidsand biochemical oxygen demand. These would include municipal wastewatertreatment facilities as well as a variety of commercial and industrialbiological treatment process as used, for example, in the foodprocessing industries, restaurants, and the like.

Furthermore, the process of the invention can be used to treat sludgesand microbial biomasses resulting from a wide variety of Multi-StageActivated Sludge (“MSAS”) and Biological Nutrient Removal (“BNR”)processes. In general MSAS and BNR processes have been designed andapplied to nutrient containing organic wastewater streams such asmunicipal wastewater, food processing wastes, or animal manure wastesstemming from confined animal feeding operations (“CAFOs”), to reducenutrient pollution resulting from the discharge of excess nitrogen andphosphorus into the environment.

As described above MSAS and BNR processes also produce an excessmicrobial biomass which is a result of the MSAS or BNR treatment processand which needs suitable final disposal. In general, BNR processes focusprincipally on the treatment and removal of nitrogen and phosphoruswhereas MSAS processes also focus on the removal of organic constituentscomprising Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand(COD). These objectives are usually accomplished with separatebiological processes but can often be combined in one treatment system.

Nitrogen is biologically removed from organic and waste streams througha process of nitrification and denitrification. The nitrificationprocess step involves the oxidation of the nitrogen in ammonia, ammoniumions, or organic nitrogen containing compounds such as proteins, nucleicacids, or the like. The nitrogen is first oxidized to nitrite by one setof autotrophic bacteria generally characterized by the Nitrosomasspecies, and then to nitrate by a second set of autotrophic bacteriagenerally characterized by Nitrobacter species. The oxidation processsteps require that at least some oxygen be present in the environment ofthe bacteria and the ammonia/organic nitrogen substrate.

The denitrification process step then converts the nitrite or nitrateinto dimolecular nitrogen gas which is then discharged to atmosphere.This process generally occurs in the absence of oxygen, or inenvironments containing very low oxygen concentrations, which stimulatesthe denitrifying bacteria to seek the oxygen that is chemically bound inthe nitrite and nitrate formed by the nitrifying bacteria. A wide rangeof bacteria have the capability to perform denitrification processes.

Thus, the conventional nitrification-denitrification process requiresthat the waste stream containing the nitrogen be exposed to both anaerobic and an anaerobic environment. It has also been found that thenitrification-denitrification process can work if an anoxic environmentis substituted for the aerobic environment conventionally used. In thiscase, free molecular oxygen does not have to be present in the specifiedenvironment, however, some other form of electron acceptor must beavailable to serve as an electron acceptor for the oxidation of theammonia. An example of this process would be the anaerobic ammoniumoxidation (“Anammox”) process.

Both the nitrification and denitrification processes are accompanied bycell growth of the appropriate bacteria and hence, these processes alsoproduce an excess microbial biomass or sludge which must be periodicallyremoved from the treatment system. The growth and reproduction of thesemicroorganisms limits the amount of ammonical and organic nitrogen thatcan be converted into dimolecular gas as some of the nitrogen isretained within the bacteria themselves. Generally this limits theconversion of ammonical and organic nitrogen into dimolecular nitrogengas to less than 80 percent, often less than 60 or 70 percent of thetotal influent nitrogen. The rest must be disposed of in the form ofsludge or microbial biomass.

In accordance with an embodiment of the present invention, thepercentage of influent ammonical and organic nitrogen which can beconverted into diomolecular nitrogen gas can be substantially increasedto 95 to 98 percent. This is accomplished by feeding the microbialbiomass comprising Nitrosomas, Nitrobacter, denitrifiers, and relatedspecies to various higher animals and then returning the wastes excretedby these higher animals back to the nitrification-denitrificationtreatment system. The higher animals will remove a small fraction of thenitrogen contained within the bacteria and assimilate it into their cellmass. The rest will be excreted but it will now be in a form which thenitrification-denitrification system can further process. This resultsin the conversion of much of the recycled nitrogen into dimolecularnitrogen gas that can then be discharged into the atmosphere.

The second process central to BNR, and often to MSAS, concerns theremoval of phosphorus from waste streams. Phosphorus, like nitrogen, isan essential element in biological organisms, and hence will be taken upinto a biological cell mass as biological organisms grow and reproduce.In BNR processes, this accumulation of phosphorus is enhanced byestablishing varying environmental conditions which the bacteria areexposed to in an alternating manner. Thus, bacteria which are exposed toalternating aerobic and anaerobic environments, or aerobic and anoxicenvironments, will exhibit luxury phosphorus uptake into the bacterialbiomass in the aerobic zone. This means that bacteria in the aerobiczone will remove more phosphorus than they need for growth andreproduction in the aerobic zone, and will store this excess phosphorusas polyphosphate. When the organisms are then exposed to anaerobic oranoxic conditions, they will use this stored polyphosphate as an energysource.

If this microbial biomass containing the stored polyphosphate is removedfrom the aerobic zone of the wastewater treatment system, it will removeincreased amounts of phosphorus when compared with conventionalbiological processes that do not contain alternating aerobic andanaerobic/anoxic environments. Thus, removal of part of the microbialbiomass is essential for all biological phosphorus removal processes.

In the process of the invention, if the bacteria containing excessphosphorus stored as polyphosphate are fed to higher animals, then someof the phosphorus will be retained in the bodies of the higher animalsand some will be excreted by these animals. Removal of the higheranimals from the treatment process will thus constitute removal of someof the phosphorus from the wastewater stream. The phosphorus excreted bythe higher animals can then be returned to the wastewater treatmentsystem where it will again undergo the treatment process.

This process can be enhanced if the microorganisms, and in particularthose microorganisms containing extra phosphorus stored aspolyphosphate, are fed either to vertebrate higher animals, or to aseries of invertebrate animals which are in turn fed to vertebrateanimals. This occurs because the bones and shells of vertebrate animalscontain large quantities of calcium phosphate and hydroxyapatite whereasthe shells of invertebrates contain mostly calcium carbonate. Given thatthe soft tissues of both vertebrates and invertebrates containapproximately similar concentrations of phosphorus, the preferentialremoval of vertebrate animals will increase the fraction of phosphorusremoved per unit of body weight of the animals removed from thetreatment process.

Given that there are many BNR processes which remove both nitrogen andphosphorus, the process of the invention can be used in conjunction withsuch processes to also remove both nitrogen and phosphorus. If excessiveamounts of nitrogen are discharged to atmosphere as dimolecular nitrogengas, then there may not be sufficient quantities of nitrogen to generatesufficient higher animal biomass to meet desired phosphorus removallevels. In such cases, chemical precipitation of phosphorus, for examplewith a metallic salt such as ferric chloride, may be required for finaleffluent discharge. Treatment with metallic salts is often a techniqueused in MSAS systems for removal of phosphorus. In such cases themetallic salt is usually added to one or more of the activated sludge orother type bioreactors and then the resulting residue containingprecipitated phosphorus is removed with the excess sludge.

Various embodiments of the process of the invention utilize modularenvironments for the growth of microorganisms and invertebrates. Inthese cases, microbial biomasses or biosolids containing microorganisms,and in particular bacteria, are introduced into such modularenvironments, wherein they are retained, wherein additionalmicroorganisms may be grown, and wherein many of such microorganisms maybe consumed by higher organisms such as invertebrates or vertebrates. Inthese embodiments of the process of the invention, the modularenvironments act as filtration and wastewater treatment systems.

One such modular process environment, called an irrigated environment,100, is shown in FIG. 1. The irrigated environment is connected in fluidcommunication to a treatment or production system such as an activatedsludge wastewater treatment system, a biological nutrient removaltreatment system, a confined animal facility operation, a foodprocessing facility, or the like. The irrigated environment receives aninfluent stream 105 from the treatment or production system and returnsa treated effluent stream 195 back to that treatment or productionsystem. The irrigated environment may also send, via communicationchannel 185, the treated effluent stream to another treatment system ormay discharge part, or all, of the treated effluent stream as a finaleffluent.

The irrigated environment may include an irrigated body of mediaincluding biodegradable materials such as wood chips, sawdust,agricultural wastes, and the like, or non-biodegradable materials suchas plastic media structures, sand, or the like. The media is arranged ina pile or stack, and may be contained in a tank, bunk silo, or otherstructure which bounds the media and contains it in a defined area. InFIG. 1, this constrained media area is shown as 110. Aqueous liquidscontaining microbial biomasses and/or biosolids are introduced at thetop of such a body of material and allowed to trickle down through themedia thereby exposing the contained biomasses, biosolids, and anyaccompanying soluble organic material or nutrients, to additionalmicroorganisms and invertebrates which may consume, attach, or otherwiseassist in removing them from the aqueous liquid.

Once the aqueous liquid has passed through the body of media it may passthrough a selector device 120 to remove any larger invertebrates oraggregates of microorganisms, and then is delivered to a vessel, tank,or the like shown in FIG. 1 as 130. The removed invertebrates oraggregates of microorganisms are collected in an Invertebrate Collector140. While in the tank 130, the liquid may be aerated or subjected toother treatment. Some fraction of this liquid is then recycled via flowpath 135 back to the top of the irrigated environment media area 110.Another part of this treated recycle stream may be returned to theoriginal treatment or production system via flow path 195. Usually theserecycle functions are performed by a pump 133. The non-recycled liquidin 130 may be discharged out of the irrigated environment module viaflow path 185 and may be sent to another treatment system, may bedischarged as an effluent stream, or may be split between a combinationof these alternatives.

A second modular environment, called a submerged environment 200, isshown in FIG. 2. As is the case for FIG. 1, the submerged environment isconnected to a treatment or production system such as an activatedsludge wastewater treatment system, a biological nutrient removaltreatment system, a confined animal facility operation, a foodprocessing facility, or the like. The submerged environment receives aninfluent stream 105 from the treatment or production system and mayreturn all or part of the treated effluent stream back to that treatmentor production system via pump 223 and flow path 225. The submergedenvironment may also send the treated effluent stream to anothertreatment system or may discharge part or all of the treated effluentstream as a final effluent.

The submerged environment may also include a body of media consisting ofbiodegradable materials such as wood chips, sawdust, agriculturalwastes, and the like, or of non biodegradable materials such as plasticmedia structures, sand, or the like. The media may be contained withinat least one, and optionally a plurality of, tanks, ponds, lagoons, orother structures capable of holding water. In certain configurations,the body of media may be arranged in nets, baskets, pens, or othercontainment structures which allow liquids to pass through the media butretain the media itself in a constrained volume. In FIG. 2, the body ofmedia and water holding structure is shown as 210. Optionally, multiplecontainment structures, such as a plurality of nets, may house the bodyof media 210 housed within a water holding structure. Optionally, thewater holding structure 210 may be a rectangular tank and the multiplecontainment structures are oriented in such a manner that liquid willflow through one of, or a series of, the containment structures. Othergeometric versions of 210 may be used that accomplish this sequentialflow result.

Aqueous liquids containing microbial biomasses and/or biosolids areintroduced at one end or side of a series of such containment structureslocated within the body of media and water holding structure 210 and areallowed to flow through the media thereby exposing the containedbiomasses, biosolids, and any accompanying soluble organic material ornutrients, to additional microorganisms and invertebrates which mayconsume, attach, or otherwise assist in removing them from the aqueousliquid. The liquid then exits the body of media 210 and passes through aselector device 220 to remove any larger invertebrates or aggregates ofmicroorganisms which may be present in the body of media and waterholding structure 210. These invertebrates or aggregates ofmicroorganisms may be collected in organism collector 240.

Some of the liquid that passes through the selector may be pumped backto the treatment or production system by Pump 1, as shown in FIG. 2. Theremainder of the liquid may be delivered to a vessel, tank, or the like,shown in FIG. 2 as 250. In some cases the selector device 220 may bemodified so that invertebrates or fish grown in 210 may flow by gravityinto 250. In this case, larger organisms such as fish may be grown inthe receiving tank or vessel 250. Such fish may then consume theinvertebrates as food.

While in the vessel 250, the liquid may be aerated or subjected to othertreatment. Some fraction of this liquid may be recycled back to theinfluent of the submerged environment water holding structure 210. Thisrecycled liquid may be collected from the bottom of the vessel 250 by apump 253 such that it may collect the settleable solids that may havecollected at the bottom of 250, or the recycled liquid may be collectedfrom a space above the bottom of 250 by a second pump 256. Both pumps253 and 256 will discharge the collected liquids at the influent end ofthe water holding structure in 210. A flow equal to the influent fromthe treatment or production system minus the return to such system andevaporative losses is discharged out of the submerged environmentalmodule 200 via an overflow line 255 from 250. As this also constitutes atreated effluent stream, the flow may be returned back to that treatmentor production system, may be sent to another treatment system, or may bedischarged as a final effluent.

FIG. 3 shows one configuration of a containment structure 300 that maybe placed in a version, such as a rectangular version, of the body ofmedia and water holding structure 210. In this embodiment, wood chips,or other similar media, are placed in an inverted trapezoidal cage orpen 310 within 300 that is bounded by a porous surface such as a net orgrate. This separates the wood chips or other media from water zones320, which are also within 300. The cage or pen is placed in a tank sothat all influent flow 305 must pass through the cage or pen prior toexiting the system as an effluent 315. There may be several or many suchcages or pens arranged in a rectangular tank version of 300 so that theinfluent must pass sequentially through each cage or pen 310 prior toexiting the system as an effluent stream. Aeration is usually suppliedto 300 via diffusers 328 or the like.

A third modular environment, called a combined environment, combinesboth the irrigated environment shown in FIG. 1 and the submergedenvironment shown in FIG. 2. One such combined environment is shown as400 in FIG. 4. In this case, the combined environment is also connectedto a treatment or production system such as an activated sludgewastewater treatment system, a biological nutrient removal treatmentsystem, a confined animal facility operation, a food processingfacility, or the like. The combined environment receives an influentstream 105 from the treatment or production system and may return one ormore treated effluent streams 910 or 920 back to that treatment orproduction system. The combined environment 400 may also send via flow930 all or part of the treated effluent stream to another treatmentsystem or may discharge part or all of the treated effluent stream as afinal effluent.

In the combined environment shown in FIG. 4, the influent from thetreatment or production system comprising liquids and/or microbialbiomasses or biosolids containing microorganisms, and in particularbacteria, is delivered to the top of an irrigated constrained media area110 which is similar to the irrigated constrained media area asdescribed relative to FIG. 1. Recycle liquids from a recycle sump 130are also introduced to the top of the constrained media area 110. Liquidthen flows through 110, passes through an organism selector 120 toselectively remove invertebrates or higher animals which are present inthe combined environment 400 and/or constrained media area 110. Liquidsubsequently passes into 130 and is then recycled via 135 back to thetop of 110. This recycle flow usually is pumped by pump 133 and may alsobe diverted back to the treatment or production system via flow path910.

Excess liquid in recycle sump 130 overflows by gravity into tank 210which may be a submerged containment structure, as described relative toFIG. 2. Flow travels through 210 and then overflows into an organismselector 220 for selective removal of invertebrates or higher animals,as discussed above. The effluent from the selector 220 may be returnedto the treatment or production system via flow path 920, or may be sent,with or without invertebrates and/or fish, to an additional tank 250 asdescribed relative to FIG. 2. Some flow from the bottom of 250 may bepumped back to the top of 110 by pump 253, transferring settleablesolids back to constrained media area 110. Other flow from 250 may bepumped back to the influent of 210 by pump 256. Any excess liquid volumein 250 overflows by gravity as a final effluent via flow path 930. Anyorganisms collected by the selector 120 and sequestered in 140 may beintroduced into 250 where they may be consumed by fish living in 250.

In various embodiments of the process of the invention, the processesdescribed by FIG. 1, 2, or 4 can be utilized as Bioreactor Systems whichare generalized methods of treating sludges from standard activatedsludge processes, Multi-Stage Activated Sludge (MSAS) processes, variousbiological nutrient removal (BNR) processes, or similar biologicalprocesses, for municipal, agricultural, or industrial wastewatertreatment facilities. One such embodiment is shown in FIG. 5.

Referring to FIG. 5, this embodiment comprises an activated sludgemunicipal waste treatment system including a bioreactor 510, a clarifier520, a Return Activated Sludge (RAS) line 525, a Waste Activated Sludge(WAS) line 527, a wastewater influent 505, and an effluent stream(Effluent #1) 585. These terms and the activated sludge process are wellunderstood by a person skilled in the art of wastewater treatment. Inthis embodiment, the waste stream from the activated sludge system isintroduced into a Process Environment system 900. Hereafter a ProcessEnvironment will refer to any one of: the Irrigated Environment 100 asdescribed by FIG. 1; the Submerged Environment 200 described by FIG. 2;the Combined Environment 400 described by FIG. 4; or similarconfigurations of possible modular environments for the growth ofmicroorganisms and invertebrates as described in the process of theinvention.

In the embodiment of the process of the invention described by FIG. 5,the Process Environment will refer to the Combined Environment 400 asdescribed by FIG. 4. The waste activated sludge stream 527 from theactivated sludge process comprises the influent to the combinedenvironment 400 as described in FIG. 4. Specifically it is the influentstream 105 to Tank 110 as shown in FIG. 4. This influent stream isprocessed by the Process Environment 900, with the flow path of therecycle loop 135 pumped by pump 133 as shown in FIG. 4, is subsequentlyreturned to the bioreactor as described with reference to FIG. 5 viaflow path 910. The organism selector 220 return to system flow 225, asshown in FIG. 2, is also returned to the bioreactor in FIG. 5 via flowpath 920. The FIG. 4 effluent from Tank 250 becomes the 930 Effluent #2flow in FIG. 5.

Periodically, the media in the modular environments comprising theProcess Environments, and in particular the media in Tanks 110 or 210 asdescribed relative to FIG. 1, 2, or 4, may need to be replaced. This isparticularly true for biodegradable media such as wood chips, sawdust,agricultural wastes, and the like, but may also be the case for plasticor other inert media which may become damaged, compacted, or otherwiserendered ineffective during operation of the modular environment.

In the case where biodegradable media is used, the containmentstructures used within the irrigated or submerged environments asdescribed relative to FIG. 1, 2, or 4 may be removed and replaced withsimilar structures containing new media. Alternatively the media withinsuch containment structures may be mechanically or hydraulically removedby various mechanisms and replaced with new media.

Once the used media has been removed from the modular environments,residual organisms may be separated from the removed media by washing,screening, shaker conveyor, or the like. Alternatively, the organismsmay be induced to leave the media through their own capacity for moving.This could include their capacity to crawl, swim, fly, or the like.

After some or all of the resident organisms have been removed from theused media, it may then be used as a substrate for other processes suchas energy production or used as a byproduct for soil abatement, mulch,or material manufacture. Relative to the energy options the materialcould be used as a substrate for biofuel production via pyrolysis,gasification, or the like, or it could be burned directly to produceheat and steam.

In the embodiment of the process of the invention as shown in FIG. 5,the activated sludge process can be replaced with any Multi-StageActivated Sludge (MSAS) or Biological Nutrient Removal (BNR) process, orany other biological treatment process, which produces a biologicalsludge as a waste product of the process. Also the modular environmentas described relative to FIG. 4 could be replaced by either of themodular environments described relative to FIG. 1 or 2 or to othermodular environments capable of serving similar functions.

In another embodiment of the process of the invention, the processesdescribed by FIG. 1, 2, or 4 can be combined with generalized methods oftreating animal manures or other similar waste streams. FIG. 6 shows onesuch embodiment.

The system of FIG. 6 includes a barn or other structure for housinganimals and associated structures for processing animals or animalbyproducts such as milk, commonly called a Confined Animal FeedingOperation or CAFO; a solids separation system that removes some of thesolids from the liquids emanating from the CAFO; a treatment systemcalled a Bioreactor System which processes in some manner the liquidsafter they are separated from some of their constituent solids; and aProcess Environment that further processes the liquids and solids fromthe treatment system and that may also utilize solids from theseparator.

In one embodiment of the invention as shown in FIG. 6, the CAFO barn 600would house dairy cows and the associated milking parlor or would housea cattle raising operation. Manure and associated wash waters andwastewaters would flow through a solids separator 610 such as a screen,screw press, or similar piece of mechanical equipment that wouldseparate the waste stream into a solid component 615 and a liquidcomponent 617. The liquid effluent 617 from the solids separator 610passes into a Bioreactor System 620 where it would be subjected totreatment with a microbial process such as a regular or low oxygennitrification-denitrification system. This Bioreactor System 620 woulddrive significant quantities of nitrogen to atmosphere as dimolecularnitrogen gas and would encapsulate significant quantities of phosphorusinto a particulate or microbial cell mass such that it could be removedfrom the liquid by appropriate mechanisms.

Liquid from the Bioreactor System 620 could be recycled back to the barnfor flushing via flow path 625 or could be recycled back to, and bemixed with, the manure stream emanating from the barn via flow path 627.This mixture may then be sent to the solids separation unit. The liquideffluent from the solids separation unit may then flow into theBioreactor System 620.

An effluent stream from the Bioreactor System 620 may flow or be pumpedinto a Process Environment 900, such as described in FIG. 5. TheBioreactor System effluent stream may enter the Process Environment asan influent stream to constrained media tank 110, as described in FIG.4. Output streams from the Process Environment could then be returned tothe Bioreactor System 620. These would include a stream 910 emanatingfrom the irrigated module in the Process Environment, or a stream 920emanating from the submerged module in the Process Environment, or both.A final effluent stream 930 emanating from the Process Environment wouldthen be sent to another treatment process or to land application or tosome other method of disposal.

In the embodiment of the invention as described in FIG. 6, the mediaused in constrained media tank 110 and tank 210, as described in FIG. 4,could include a base of wood chips. In some cases, particularly withrespect to Tank 110, a top or internal layer of separated solids fromthe solids separator shown in FIG. 6 may be incorporated within theconstrained area. The effluent stream from the bioreactor would then beapplied at the top of Tank 110 in a manner and at a flow rate such thatmany fine solids, microbial biomasses, and/or biosolids contained withinthe bioreactor effluent would be retained within the constrained area ofthe irrigated module in Tank 110. Many of the fine solids, microbialbiomasses, and/or biosolids which passed through the constrained areawould end up in Tank 130, as described in FIG. 4, and would be returnedback to the top of Tank 110 by pump 133 where they would again passthrough the constrained area with additional fine solids, microbialbiomasses, and/or biosolids being removed from the liquid stream. Someof the tank 130 pumped stream could be returned to the bioreactor viaflow path 910 for further processing.

The effluent stream from Tank 130 then flows through Tank 210 whereadditional fine solids, microbial biomasses, and/or biosolids areremoved. After passing through a selector, as described above, some ofthe effluent from Tank 210 will be returned back to the bioreactor vialine 920 for further processing. The rest of the effluent from Tank 210will be sent to Tank 250. Some of the Tank 250 effluent will then bedischarged as a final effluent 930.

The invertebrate and vertebrate organisms which reside within theProcess Environment will consume some of the microbial biomass containedwithin the influent stream coming from the Bioreactor System. Thesehigher organisms usually will range from protozoa, to any of a varietyof invertebrates such as worms, insects, snails, crustaceans, or thelike, or to various vertebrates such as fish or turtles. Occasionally,other vertebrate animals such as amphibians, reptiles, birds, or mammalsmay be used.

Once the biosolid or microbial biomass has been consumed by the higherorganisms, part of the cellular structures of the microorganisms will bedestroyed by the ingesting organism, and some of the carbonaceousmaterial and nutrients will be converted into the biomass of theconsuming higher organisms for growth and reproduction. The remainder ofthese materials will be excreted by the higher organisms.

In this embodiment of the process of the invention, some of the nitrogenthat is bound in the microbial cells in the Bioreactor System effluentwill be converted back into ammonium ions or free nitrogen containingcompounds such as amino acids, nucleic acids, peptides, proteins, orother organic nitrogen containing compounds. By returning thesematerials back into the Bioreactor System, much of this nitrogen can beacted on in the Bioreactor System and converted into dimolecularnitrogen gas. This would not be the case for the whole living cellscomprising the microbial biomass itself.

In the case of phosphorus, the use of appropriate vertebrate organismswithin the combined environment will allow a disproportionately highamount of phosphorus, when compared with nitrogen, to be removed fromthe system. The incorporation of more phosphorus than nitrogen intothese organisms will help compensate for the differential removal ofnitrogen as dimolecular nitrogen gas in the bioreactor. If excessiveamounts of nitrogen are discharged to atmosphere as dimolecular nitrogengas, then there may not be sufficient quantities of nitrogen to generatesufficient higher animal biomass to meet desired phosphorus removallevels. In such cases, chemical precipitation of phosphorus, forexample, with a metallic salt such as ferric chloride, may be requiredfor final effluent discharge.

These processes will act to reduce the total volume and weight of solidmaterial within the bioreactor and will also reduce the total volume andweight of solid material, nitrogen, and phosphorus which will becontained within the system effluent and which ultimately must bedisposed of by land application or other similar means.

As described with reference to FIG. 5, the media in the modularenvironments comprising the combined environment, and in particular themedia in Tanks 110 or 210 as described relative to FIG. 1, 2, or 4, mayneed to be periodically replaced. This can occur by removing thecontainment structures used within the irrigated or submergedenvironments as described relative to FIG. 1, 2, or 4, and replacingthem with similar structures containing new media. Alternatively themedia within such containment structures may be mechanically orhydraulically removed by various mechanisms and replaced with new media.

Once the used media has been removed from the modular environments,residual organisms may be separated from the media itself by washing,screening, shaker conveyor, or the like. Alternatively, the organismsmay be induced to leave the media through their own capacity for moving.This could include their capacity to crawl, swim, fly, or the like.

After some or all of the resident organisms have been removed from theused media, it may then be used as a substrate for other processes suchas energy production or used as a byproduct for soil abatement, mulch,or material manufacture. Relative to the energy options the materialcould be used as a substrate for biofuel production via pyrolysis,gasification, or the like, or it could be burned directly to produceheat and steam.

The higher organisms which result from the process of the invention canbe collected for removal or other use such as feed for animals, soilconditioners, or the like.

In accordance with another embodiment of the present invention as shownin FIG. 7, a Multi Stage Activated Sludge System (MSAS) is used as aBioreactor System 620 as shown in FIG. 6. FIG. 7 shows an MSAS 700 inwhich a first stage activated sludge process, comprising a bioreactor710 and a clarifier 720, would serve to remove a significant fraction ofthe Biochemical Oxygen Demand (BOD) from the influent flow 705. Thisfirst stage activated sludge process includes a return activated sludgeline 715 and a waste activated sludge line 717, as described relative toFIG. 5. The effluent from this first stage activated sludge processflows into a second stage activated sludge process, also comprising abioreactor 730 and a clarifier 740, which may perform a nitrificationfunction on the waste stream. This second stage activated sludge processmay also include a return activated sludge line 735 and a wasteactivated sludge line 737, as described relative to FIG. 5. The totalBioreactor System 700 has an effluent flow 745 and would also drivesignificant quantities of nitrogen to atmosphere as dimolecular nitrogengas. The system could be coupled to a metallic salt system that wouldencapsulate or precipitate significant quantities of phosphorus into aparticulate form or a microbial cell mass such that it could be removedfrom the liquid by appropriate solids removal mechanisms.

In the embodiment incorporating an MSAS 700, as shown in FIG. 7, theBioreactor System 620, as shown in FIG. 6, recycles flow back to thebarn 625, or to the stream emanating from the barn prior to the solidsseparation system 627. The Waste Activated Sludge streams from both thefirst and second stage systems, 717 and 737, would be sent to Tank 110in the Irrigated Module in The Process Environment (as shown in FIG. 4as a part of FIG. 6). The Effluent flow 745 from the MSAS as shown inFIG. 7 would be sent to Tank 210 in the Submerged Module in The ProcessEnvironment (as shown in FIG. 4 as a part of FIG. 6). The flows 910 and920 from the Process Environment could be returned, if desired, to theBioreactor System and discharged into the second stage nitrifyingbioreactor, 730. Otherwise this embodiment of the process of theinvention will function in a similar manner as the first such embodimentdescribed relative to FIG. 6.

In a further embodiment of the process of the invention, FIG. 8 shows anextension to the generalized method of treating animal manures asdescribed in FIG. 6. In this case, the removal of a significant fractionof the fine solids and the biosolids from the initial Bioreactor Systemeffluent allows for efficient further processing of the liquid viaadditional treatment processes.

As shown in FIG. 8, a second low oxygen nitrification-denitrificationBioreactor System is added to the process as described in the firstpreferred embodiment described relative to FIG. 6. The system of FIG. 8further includes a barn 600, and solids separator 610. Recycle flowsfrom the bioreactor used to flush the barn 625 or dilute the manurestream exiting the barn prior to solids separation 627, and theBioreactor System 620, are the same as those described relative to thefirst preferred embodiment of FIG. 6. Process Environment #1 900 wouldbe the same as the Irrigated Environment 100 as shown in FIG. 1. In thiscase, the recycle will be returned from Process Environment #1 900 toBioreactor System #1 620, and this would be the irrigated module returnflow path 910. The Process Environment #1 effluent flow 930 would serveas the influent flow to the second Bioreactor System 810.

The significant reduction in solids achieved by Process Environment #1allows Bioreactor System #2 810 to be configured differently than ispossible with Bioreactor System #1 620. Because of the lower solidsconcentration in Bioreactor System #2 810, it becomes possible to grow amicrobial floc which could settle by gravity or possibly be concentratedby a form of dissolved gas (air) floatation.

In the case of gravity settling, Bioreactor System #2 would have twounit processes arranged in a manner similar to an activated sludgetreatment system. Thus a mixed and partially aerated suspended growthzone would be followed by a quiescent zone or clarifier in which themicrobial floc could settle and be concentrated. The concentrated flocmay then be returned back to the suspended growth zone. Excess solidscould be returned back to Bioreactor System #1 620 via flow path 817.

In the case of floatable floc, a suspended growth zone would be followedby a Dissolved Air Floatation (DAF) unit in which tiny bubbles of gaswould float and concentrate the floc so that it could be captured,removed from the DAF unit, and returned to the suspended growth zone.Similar to the discussion of the settlable floc, the excess DAF floccould be returned back to Bioreactor System #1 via flow path 817.

In one embodiment, the effluent from Bioreactor System #2 could serve asa first system effluent 815, or it could serve as an influent flow 819to a second Process Environment, 902. An effluent flow 932 out of thesecond Process Environment 902, could also serve as a second systemeffluent, or the total system effluent could be a combination of the twoeffluent flows, 815 and 932.

Process Environment #2 902 could have the same configuration as system200 in FIG. 2 with the irrigated module return to system line 910(denoted as 912 in FIG. 8) returned to Bioreactor System #2 810. ProcessEnvironment #2 902 could also have the same configuration as system 400as shown in FIG. 4 with the submerged module return to system line 920shut off and the irrigated module return to system line 910 (denoted as912 in FIG. 8) returned to Bioreactor System #2 810.

Periodic replacement of the media in both combined environments willoccur as described for FIG. 6. Solids 615 from the solids separator maybe included in any of the irrigated or submerged modules in eitherProcess Environment #1, 900, or Process Environment #2, 902.

In a further embodiment of the process of the invention, an initialBioreactor System, such as Bioreactor System #1 620 in FIG. 8, may beeliminated from the entire process. This alternative is shown in FIG. 9.In this embodiment, the liquid effluent 617 from the solids separator isintroduced directly into Tank 110 in an initial Process Environment #1900 comprising 100 in FIG. 1 or 400 in FIG. 4. Alternatively, theeffluent from the barn may be sent directly to Tank 110 in ProcessEnvironment #1, 900. Recycle flow rates within Process Environment #1900 can be adjusted to accommodate for this change and the part of therecycle flow in the irrigated environment module that is returned tosystem 910 in FIG. 1 or FIG. 4, will be used as flush water 625 for thebarn, or dilution water 627 for the manure stream exiting the barn priorto solids separation if a solids separation step is used.

In the embodiment of the process of the invention as shown in FIG. 9,Process Environment #1 900 may be the Irrigated Environment 100 as shownin FIG. 1, or it may be the Combined Environment 400 as shown in FIG. 4.The Bioreactor System 810 as shown in FIG. 9 may be the low oxygennitrification-denitrification system 620 described relative to the firstpreferred embodiment of FIG. 6 or it may be the MSAS system 700 asdescribed in FIG. 7, or it may be any of a range of BNR systems orsimilar nutrient removal systems. Process Environment #2 902 may be theSubmerged Environment 200 as described in FIG. 2 or it may be theCombined Environment 400 as described in FIG. 4 or some other similarsuch environment.

In accordance with yet another embodiment of the process of theinvention, as generally described by FIG. 9, is shown in FIG. 10. Inthis embodiment, manure 2 from one or more animals such as a cow, pig,goat, sheep, chicken, turkey, fish, or other animal is introduceddirectly to a process environment 102 comprising an irrigated biofilter110 such as a trickling filter or the like and a recycle sump 130. It isunderstood herein that the direct introduction of the manure 2 into theprocess environment 102 may be provided by mechanical means such aspiping or mechanical shoveling, and the like. This process environmentis a specific case of the general process environment previouslydescribed in FIG. 1, but the invertebrate selector 120 and collector 140are optional and the return flow 195 is not used since manure isdirectly introduced into the system. Aeration 328 may be introduced inthe recycle sump 130 by conventional means, as discussed above. Themanure solids will be retained in the irrigated biofilter 110 and theaerated recycle sump 130 will promote the growth of aerobic microbesthat will consume the soluble biochemical oxygen demand (BOD) of theinfluent manure stream. The consumption of the BOD may occur in therecycle sump or in the irrigated biofilter itself.

Overflow from the irrigated biofilter recycle sump 130 flows into abioreactor system including an aerated nitrifying bioreactor 960, aclarifier 970, and an anoxic or anaerobic denitrifying bioreactor 980.The nitrifying bioreactor 960 includes at least a suspended growth zonewherein nitrifying microbes form a floc which can settle out from theliquid once they are passed to the clarifier. The underflow 972 from theclarifier 970 will contain a higher concentration of solids than willthe effluent 973 from the clarifier 970. This underflow 972 will bereturned to the nitrifying bioreactor via flow path 974 to concentratethe nitrifying biomass. Excess solids may be returned via flow path 976to the influent to the irrigated biofilter. The nitrifying biomass willconvert ammonia and organic nitrogen into nitrite and nitrate.

The effluent 973 from the clarifier 970 flows into a furtherdenitrifying bioreactor which is not aerated and which may be anoxic oranaerobic. This bioreactor may contain a suspended microbial floc or itmay contain a fixed media such as wood chips which support an attachedbiofilm. Some of the microbes in the suspended floc or attached biofilmwill denitrify the soluble nitrate and nitrite produced within theaerated nitrifying bioreactor. This denitrification will result in thedischarge of dimolecular nitrogen gas 981 to the atmosphere.

The effluent from the denitrifying bioreactor 980 will flow into afurther process environment comprising a submerged biofilter containingwood chips or other suitable media which is configured similarly to theway that Tank 210 in FIG. 2 and FIG. 3 was configured. This submergedbiofilter will function in the same manner as Tank 210 and this functionis the same as that described relative to Tank 210 in FIGS. 2 and 3.Aeration will be supplied to all or part of the submerged biofilter. Inthe submerged biofilter some of the solids, nutrients, and BOD that arein the effluent from the denitrifying bioreactor will be removed and/orconsumed by microbes residing on the surfaces of the wood chips. Thefinal effluent 982 from the submerged biofilter will be the finaleffluent from the system and a fraction of this effluent may be recycledvia line 984 back to the influent to the submerged biofilter.

If it is desirable to remove additional phosphorus to that removed bythe various microbial biomasses, a metallic salt 991 such as ferricchloride, ferrous sulfate, or the like, may be added to the aerobicnitrifying bioreactor or to the submerged biofilter. This willprecipitate phosphorus into an insoluble salt which may be removed fromthe system with the wood chip residues. Alternatively, a metallic saltmay be added to the final effluent where a phosphorus precipitate willbe formed and this can be recycled via line 984 back to the influent tothe submerged biofilter and removed with the wood chip residue.

Periodically all or part of the wood chips used in the irrigatedbiofilter, anoxic bioreactor, or submerged biofilter will be replaced.The partially degraded chips may be washed to remove any remainingnutrients, microbial cells, and invertebrates. The remaining chips willbe allowed to drain and then will be dried. The residual chips can thenserve as a renewable energy source and can be burned to provide heat orsubjected to various other treatments such as pyrolysis or gasificationto produce a burnable fuel.

Alternatively, the residual chips may be removed from the system withoutbeing washed. The residual wood chips may then be dried and burned orused as a substrate for gasification, pyrolysis, or similar processes.Alternatively, the chips could be dried and then screened to separate afine particulate fraction containing nutrients and a coarse particulatefraction which contains a lower relative amount of nutrients and thelarger residual wood chips. The fine particulate fraction may be used asa soil amendment or plant growing medium and the large particulatefraction may also be used as a soil amendment, may be used as a mulch,or may be burned to provide heat or used as a substrate to produceburnable fuels.

In some cases in which the chip residue is burned, stack gases can bescrubbed from the incineration process and residual materials such assoot particles and nitrogen and sulfur oxides will be removed from thestack gases and trapped in a liquid scrubber stream. This scrubberstream may then be returned to the system for further removal andtreatment of these particles and materials.

Since nitrogen and phosphorus are treated with different mechanismswithin the process of the invention it is possible to control therelative concentrations of nitrogen and phosphorus within the solid woodchip residues and the ash fraction of any such residues that areincinerated or otherwise processed. Consequently, there are a variety ofuses for such wood chip or ash residues comprising soil amendments,potting soils, fertilizers, and the like.

While the present invention was described with reference to severaldistinct embodiments of a treatment process, those skilled in the artmay make modifications and alterations to the present invention withoutdeparting from the scope and spirit of the invention. Accordingly, theforegoing detailed description is intended to be illustrative ratherthan restrictive. The invention is defined by the appended claims, andall changes to the invention that fall within the meaning and the rangeof equivalency of the claims are embraced within their scope.

What is claimed is:
 1. A process for wastewater treatment, comprising: awaste stream comprising organic constituents; and a process environmentcomprising a solid media and microbes, the process environment having afluid inlet for receiving the waste stream therein, the solid mediacomprising biodegradable non-pyrolized solid wood material, the solidmedia supporting growth of the microbes, wherein at least some of theorganic constituents within the waste stream are removed from the wastestream within the process environment, and wherein the processenvironment has an influent and an effluent, wherein at least a portionof the effluent of the process environment is directed to the influentof the process environment through the fluid inlet.
 2. The process ofclaim 1, wherein the process environment is an irrigated environment. 3.The process of claim 1, wherein the process environment is a submergedenvironment.
 4. The process of claim 1, wherein the process environmentis a combined environment comprising an irrigated environment and asubmerged environment.
 5. The process of claim 1, wherein the wastestream is an effluent stream from at least one of an activated sludgewastewater treatment system, a biological nutrient removal treatmentsystem, a confined animal facility operation, a food processingfacility, and/or a pharmaceutical processing facility.
 6. The process ofclaim 1, wherein the waste stream comprises animal manure.
 7. Theprocess of claim 1, wherein at least some of the liquid exiting theprocess environment having a first total solids value is recycled intothe process environment for further treatment.
 8. The process of claim7, wherein the liquid exiting the process environment after beingrecycled into the process environment has a second total solids value,the second total solids value being less than the first total solidsvalue.
 9. The process of claim 1, further comprising anitrication-denitrification bioreactor in communication with the wastestream.
 10. The process of claim 9, further comprising a secondnitrification-denitrification bioreactor in communication with the wastestream.
 11. The process of claim 9, wherein the process environmentfurther comprises higher animals, and wherein the higher animals consumeat least a portion of the microbes.
 12. The process of claim 11, furthercomprising an organism collector in flow communication with the wastestream of the process environment to remove at least some higher animalsfrom the process environment.
 13. The process of claim 1, wherein thewaste stream comprises at least some solid material.
 14. The process ofclaim 1, wherein the process environment comprises an irrigatedbiofilter.
 15. The process of claim 1, further comprisingnitrification-denitrification bioreactors in communication with thewaste stream and the process environment.